Biology Review

Front 1

A motor neuron

Back 1

1)is a component of the peripheral nervous system
2) communicates signals to a muscle

Front 2

what happens immediately in response to a threshold potential being reached at the axon hillock?

Back 2

sodium enters the cell because the sodium inactivation gate is open and the sodium activation gate opens

Front 3

neuronal hyperpolariation during an action potential is caused by

Back 3

potassium ions exiting the neuron

Front 4

if a pre-synaptic neuron releases an inhibitory neurotransmitter, the ligand will

Back 4

bind to receptors on dendrites of the post0synaptic neuron and cause the cell to hyperpolarize

Front 5

while a nueron is at rest, potassium ions are able to ove passively across the membrane. Under these conditions you would predict that the potassium

Back 5

is moving out of the cell through non-gated channels

Front 6

what two things increase conduction velocity along the axon?

Back 6

greater diameter, myelination

Front 7

what correctly describes the sodium potassium pump in neurons?

Back 7

it brings two potassium ions into the cell for every three sodium ions pumped out

Front 8

what correctly describes myelin?

Back 8

1)it does not cover the nodes of Ranvier
2)it increases the conduction velocity of an axon

Front 9

what correctly describes acetylcholine?

Back 9

it is released as a result of calcium ions entering the asonal terminal

Front 10

what events require the expenditure of cellular energy to occur?

Back 10

the mjovement of calcium ions from muscle cell cytoplasm to the sarcoplasmic reticulum

Front 11

myofibrils contain:

Back 11

myosin and actin

Front 12

flex your arm and feel your bicep muscle bulge. what factors are responsible for the changes that occur in the sie and shape of the muscle?

Back 12

the sarcomere thickens because actin filaments slide past myosin myofilaments

Front 13

in skeletal muscle, such as your biceps, tropomyosin

Back 13

can block the formation of a crossbridge

Front 14

when skeletal muscle, such as your biceps, is at rest

Back 14

myosin binding sites are not exposed

Front 15

as a direct response to depolariation of a muscle cell

Back 15

calcium is released from the sarcoplasmic reticulum

Front 16

if a skeletal muscle is going to produce the sliding filament action:

Back 16

crossbridges must form due to ATP hydrolysis at the myosin heads

Front 17

if a supply of atp is not available to akeletal muscle

Back 17

1)crossbridges could not be broken
2)rigor mortis could occur

Front 18

water in xylem of a root may have entered the plant through:

Back 18

1)the symplastic pathway
2)the apoplastic pathway

Front 19

If water entered a plant cell through the symplastic pathway, you know that:

Back 19

it moved into the cell by osmosis

Front 20

hydrogen bonds:

Back 20

1)hold different water molecules together
2)allow water to be attracted to the walls of the xylem

Front 21

tulips, daffodils, and other spring flowers that frow from belowground bulbs have begun to emerge. carbohydrates must move fromt he bulb to the new tissue aboveground in order to support it's growth. which of the following must occur at the bulb for this process to occur?

Back 21

carbohydrates get actively transported into the phloem.

Front 22

if a plant needs gas to carry out photosynthesis:

Back 22

guard cells must be turgi so CO2 can diffuse in

Front 23

the casparian strip:

Back 23

1)is hydrophobic
2)surrounds the stele

Front 24

In order for leaves at the top of a tall tree to have water delivered to them:

Back 24

water must evaporate through stomata

Front 25

what would allow plants to open their stomata?

Back 25

Low abscisic acid levels in leaves

Front 26

what describes the path of blood through the pulmonary circuit?

Back 26

right atrium->right ventricle->pulmonary arteries->pulmonary capillaries->pulmonary veins->left atrium->left ventricle

Front 27

within the vertebrate circulatory system, gas exchange occurs by:

Back 27

diffusion at capillaries

Front 28

what is a correct statement about capillaries?

Back 28

blood flow into them can be blocked by contracted (closed) precapillary sphincters

Front 29

what correctly describes hemoglobin?

Back 29

1)it increases the solubility of oxygen in blood
2)it binds oxygen cooperatively
3)CO2 can bind to it

Front 30

in response to vigorous exercise, your tissues would:

Back 30

increase their rate of CO2 production, which would cause a right-shift in an oxygen dissociation curve.

Front 31

we compared the oxygen dissociation curves for human mothers, their fetuses, and mammals adapted to high altitudes. recall that the oxygen dissociation curves for these groups differ. When comparing p50 values among these groups, which group would have the highest corresponding P02 value?

Back 31

Human mothers

Front 32

Which of the following would cause your blood pH to decrease?

Back 32

1)an increase in the rate of cellular respiration in tissues
2)an increase in the rate of CO2 production

Front 33

In your systemic circuit, carbonic anhydrase:

Back 33

assists in the production of carbonic acid.

Front 34

Replication and segregation are:

Back 34

1)coupled in prokaryotes
2)not coupled in eukaryotes

Front 35

Septum formatino and cleavage furrow formation:

Back 35

are both involved in cytokinesis

Front 36

a nucleosome is a component of:

Back 36

a eukaryotic chromosome and is made up of DNA and histone proteins

Front 37

what correctly describes chromosomal compaction?

Back 37

1)it facilitates efficient segregtion
2)it occurs during prophase

Front 38

a kinetochore is:

Back 38

made up of protein and is the site of microtubule attachment

Front 39

cyclin molecules:

Back 39

1)are produced cyclically throughout the cell cycle
2)are a component of maturation (mitosis) promoting factor

Front 40

a cell cycle checkpoint occurs:

Back 40

at the G2 to prophase transition

Front 41

during which phases of mitosis would a chromosome be composed of two chromatids?

Back 41

1)metaphase
2)prophase

Front 42

Mutants of frog cells have been ientified that produce a cyclin (b1) that does nto get normally degraded during the cell cycle. The continued presence of the cyclin blocks the production of the enzyme that normally degrades cohesins. Which phase of the cell cycle would be blocked directly in frog cells that possess this mutation?

Back 42

anaphase

Front 43

mitosis and meiosis are similar because:

Back 43

1)both involve the segregation of genetic material
2)both are followed by cytokinesis

Front 44

mitosis and meiosis differ because:

Back 44

1)sister chromatids separate in anaphase of mitosis but only separate in anaphase II of meiosis
2)chromosomes independently assort in meiosis but do not independently assort in mitosis

Front 45

Haploid cells are produced:

Back 45

1)at the end of meiosis II
2)at the end of meiosis I

Front 46

What correcly describes synapsis?

Back 46

1)it occurs during prophase I of meiosis
2)it produces a tetrad

Front 47

crossing over:

Back 47

occurs during prophase I of meiosis and results in the reciprocal exchange of genetic material between non-siser chromatids

Front 48

What is is a correct statement about meiosis I and meiosis II:

Back 48

Chromosomes condense during prophase of both

Front 49

Garden peas have 14 chromosomes. the corect way to represent a pea cell entering mitosis is:

Back 49

2n=14

Front 50

A true breeding round seed pea is crossed to a true breeding wrinkled seed pea. the progeny are all round. If the F1 progeny are intercrossed, what genotypic ratio would you expect in the F2's?

Back 50

1 homozygous dominant:2 heterozygous:1homoygous recessive

Front 51

The principle of independent assortment is illustrated by what data?

Back 51

When F2's are produced from offspring of true-breeding dominant and recessive parents in a dihybrid cross, the F2's exhibit four different phenotypes

Front 52

If an individuals genotype is AaBbCc, this individual has:

Back 52

3 loci and 6 different alleles

Front 53

A pea plant has the genotype AABbCc, and three genes assort independently. How many different gametes can this plant make?

Back 53

Equal numbers of 4 kinds of gametes

Front 54

In the followign cross upper case letters indicate a dominant allele and lower case letters the recessive allele. The alleles all assort inependently. When the cross Aa Bb Cc x aa Bb cc is made, what is the probability of getting all phenotypically recessive offspring?

Back 54

1/16

Front 55

in the following cross upper case letters indicate a dominant allele and lower case letters the recessive allele. the alleles all assort independently. when the cross Aa Bb Cc x Aa Bb Cc is made, how many different phenotypes should be observed among the offspring?

Back 55

8

Front 56

what represents a test cross?

Back 56

Y_R_ x yyrr

Front 57

In garden peas, tall is dominant to short and round seed coat is dominant to wrinkled. plant height is independent of seed shape. you cross true-breeding round tall peas to true-breeding wrinkled short peas to produce F1 offspring. Ifone of these F1 offspring is then test-crossed, what is the expected phenotypic ration among the resulting offspring?

Back 57

1 round tall:1 round short:1 wrinkled tall:1 wrinkled short

Front 58

Incomplete dominance and codominance differ because:

Back 58

in incompletge dominance, the heterozygote is intermediate between the two homozygotes and in codominance the heteroygote shows the traits of both

Front 59

when true-breeding red four o'clocks are crossed with true-breedig white four o'clocks, the offspring produced are pink. When a pink offspring is crossed witha red-flowering plant what fraction of the offspring is expected to be pink?

Back 59

1/2

Front 60

Humans have type AB blood because:

Back 60

they are heterozygous and produce two types of sugars on their blood cells.

Front 61

Sharon has type A blood, her parents had type A and type O blood. Rick has type B blood. his parents had type A and type B bood. They are expecting their first child. How many possibilities are there for the blood type of their child?

Back 61

4

Front 62

homogametic means that:

Back 62

individuals have one type of sex chromosome

Front 63

Mice have numerous genes that affect coat color. one gene has two alleles that produce either a black pigment(B) or a brown pigment (b). another gene, the C gene, is epistatic to the B gene. The wild type allele (C) produces pignment, the colorof which depends on the B gene, and the mutant albino allele (c), produces no pigment regardless of the genotype at the B locus. If you cross mice with the following genotypes Bbcc x bbCc, what phenotypic ratio do you expect in the offspring?

Back 63

1 black: 1 brown: 2 albino

Front 64

Enamen hypoplasia is a sex-linked genetic condition in which tooth enamel is normaly developed but extremely thin, making teeth particularly prone to wear and decay. The teeth of affected individuals may also have a striped appearance. A female affected by enamel hypoplasia married a man with enamel hypoplasia. All of their daughters have enamel hypoplasia, and they have one son with the condition and one son without the condition. based on this information you can conclude:

Back 64

the disease is caused by a dominant allele and the female is heterozygous

Front 65

In drosophila, the genes for cinnabar eyes (cn) and vestigial wings (vg) are both on the second chromosome. cinnabar eyes and vestigial wings are both recessive traits. Normal eyes are red and normal wings are long and straight. in dropophila, another trait, yellow body (y), is a sex-linked recessive on the X chromosome. The dominant wild type produces grey pigment to give the body a striped appearance. A true-breeding wild type male was mated to a yellow-bodied female with cinnabar eyes and bestigial wings. what is the change of a wildtype son with a yellow body being produced among all the offspring from this mating?

Back 65

1/2

Front 66

as the distance between two loci on a chromosome increases:

Back 66

1) the frequency of crossing over events between them increases
2)the number of genetically recombinant progeny in a test cross increases

Front 67

b+ vg+=6
b vg+=44
b vg=6
b+ vg=44
given these data, what can you conclude about the relative location of these two loci?

Back 67

they are on the same chromosome and 12 cm apart

Front 68

pedigree question:

Back 68

the disease is cause by an autosomal recessive

Front 69

according to the current central dogma ofmolecular biology, RNA may be used to direct the prouction of a protein. this process is called:

Back 69

translation

Front 70

the genetic code is redundant. this means that:

Back 70

some amino acids are coded for by more than one codon

Front 71

prokaryotes and eukaryotes differ because:

Back 71

1)prokaryotes couple transcriptio and translation and eukaryotes do not
2)eukaryotes may have noncoding sequences removed from RNA after it is produced and prokaryotes do not

Front 72

what do restriction fragment length polymorphisms and variable tandem nuclear repeats have in common?

Back 72

they are both difference in DNA sequences among individuals

Front 73

Neurospora could not grow unless added arginosuccinate or arginine
glutamate->ornithine->citruline->arginosuccinate->arginine
based on this info alone you could conclude that this mutant was

Back 73

deficient in enzymes necessary to convert citrulin to arginosuccinate

Front 74

the RNA holoenzyme:

Back 74

has a sigma factor that recognizes a promoter

Front 75

in eukaryotes, transcription factors:

Back 75

1)are a component of the intitiation complex
2)bind to enhancers

Front 76

if a cell had a mutation that prevented it from producint functional RNA pol I, what normal function of the cell could nto be carried out?

Back 76

The cell would be unable to produce rRNA in the nucleus

Front 77

Aminoglycosides inhibit polyA polymerase. Treatmtn of cells with aminoglycosides would disrupt:

Back 77

events following transcription in eukaryotes

Front 78

What can be used to direct the production of multiple polypeptides?

Back 78

1)one gene whose product is alternatively spliced
2)multiple genes
3)multiple transcripts

Front 79

a given tRNA molecule:

Back 79

contains an anticodon

Front 80

terminator sequences:

Back 80

cause the dissociation between RNA and DNA

Front 81

What is a correct statement about sliceosomes?

Back 81

they remove intron sequences from eukaryotic RNA

Front 82

a template strand of DNA:

Back 82

directs the production of complementary RNA base pairs in the nucleus

Front 83

In prokaryotes,what is necessary for initiation during translation?

Back 83

1) initiator tRNA
2) ribosomal binding sequence

Front 84

A polypeptide chain is released after:

Back 84

release factors enter the A site

Front 85

A ribosome:

Back 85

1)has enzymatic function
2) must decode the message in mRNA

Front 86

cycloheximide is an antibiotic that prevents the release of tRNA from the P site. Treatment of cells with cycoheximide would directly disrupt:

Back 86

the elongation phase of translation

Front 87

Peptidyl transferase:

Back 87

is located in the large ribosomal subunit and helps to forma bond between the amino terminus of the new amino acid and the carboxyl terminus of the growing chain.

Front 88

what is a correct statement about translocation?

Back 88

1)an elongation factor is required
2)GTP is required

Front 89

Uncharged tRNA molecules:

Back 89

1)may occupy the ribosomal E site
2)may occupy the ribosomal P site

Front 90

glycosylransferase A is the enzyme that adds galactosamine to the glycoproteins on blood cells. It is a polypeptie chain composed of 354 amino acids and two domains. Glycosyltransferase B is the enyme that adds galactose to the glycoproteins on blood cells. It differs from glycosyltransferase A in three amino acids
Information for the synthesis of glycosyltransferase A is stored in:

Back 90

DNA

Front 91

how many codons difer between the edited transcript of glycosyltranferase A and the edited transcript of glycosyltransferase B?

Back 91

3

Front 92

what is the maximum level of protein structure glycosylransferase A exhibits?

Back 92

tertiary

Front 93

which of the following is expected to be true aout hydrophobic ligands?

Back 93

it affects the gene expression directly

Front 94

when one of your cells is injured by a needle piercing through it, the cell releases histamines, which causes capillaries to leak fluid near the area of injury. the histamine response involved in inflammation is an example of:

Back 94

paracrine signaling

Front 95

when a protein is denatured:

Back 95

1)it loses its biological function
2)it may be correctlyrefolded with the assistance of chaperone proteins

Front 96

signal recognition particles:

Back 96

have receptors on the surface of the endoplasmic reticulum

Front 97

In muscle tissue, calcium is stored in the sarcoplasmic reticulum, the muscles version of the endoplasmic reticulum. A molcules inside the cell, such as IP3, allowes calcium release by binding to a receptor on the sarcoplasmic reticulum. The IP3 production is stimulated by the activation of a G protein. In this exapmle,IP3 is:

Back 97

a second messenger

Front 98

Ligand binding to a growth factor receptor can ltimately lead to the activation of a kinase, such a cyclin-dependent kinase. this occurs because

Back 98

1)a cascade of phosphorylation events was initiate by the ligand binding
2) the internal portion of the receptor is catalytic

Front 99

steroid hormones bind to a receptor and change its conformation. The steroid receptor complex can then bin to DNA to activate certain genes. The steroid receptor complex

Back 99

1)acts as a transcription factor
2)would bind to a promotor